Lymph node metastasis in level IIb neck dissection for clinically node-negative oral squamous cell carcinoma patients: an 11-year retrospective study.

The most common complication associated with selective neck dissection is spinal accessory nerve dysfunction and shoulder disability, which result from level IIb dissection. The main objective of this study was to evaluate the incidence of level IIb lymph node metastasis in clinically node-negative (cN0) oral squamous cell carcinoma (OSCC) patients. Patients presenting with cN0 OSCC between November 2012 and November 2023 were included retrospectively. The primary endpoint was the incidence of level IIb lymph node metastasis in these patients. A total of 389 patients (527 supraomohyoid neck dissections) who presented during the 11-year period were included in this study . The incidence of occult cervical lymph node metastasis was 25.2%. The median number of level IIb lymph nodes removed was 5.5. No metastatic lymph node was found at level IIb. The absence of metastatic involvement at level IIb and high prevalence of shoulder dysfunction caused by injury to the spinal accessory nerve during level IIb neck dissection challenges the necessity of level IIb neck dissection in cN0 OSCC.